Improvement in electric fuses



id-nited States @met admits.

Letters Patent No. 97,2411, dated November 23, 1869.

IMPROVEMENT IN ELECTRIC FUSES.

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To all whom it' may concern Be it known that I, H. JULIUS Sxu'rrr, of Boston -in the State of Massachusetts, 'have inventedan Improved ElectrieFuse and Cord; and I do hereby', dcclau'e the following to be a. full and correctdescription of the saure, reference being had to the accompanying drawings, in wlrih- Figure 1 is a'longitudinal sectional view ofthe fuse with the elecie oord attached.

My inventionconsists in the employment of novel devic and' means for securing `the wires within the fuse, combining the wires into a cord, and rendering the fuse impervious to moisture.

'The shell ofthe fuse is of wood, and, as is common with electric fuses,consists of a. cup, B, and a cylinder,

cient size -to contain all the powder which is required of the kind most easily ignited by the electric spark, while the cup may be charged with an inferiorV powder.

The cylinder of my fuse is ma'de with a shouhler at a, and is provided with a disk, (wooden disk,) b, which fits closely in the larger chamber of the receiver, asA

shown.

The wires areput through the cylinder, and secured by pushing the disk between them into the cylinder as tar as the shoulder, as shown.

The ends ofthe wires may be uncovered before the disk is pushed into its place; but care must be taken that they are protected by the insulating-covering through the smaller part of the cylinder as far as the shoulder b.

The chamber in the cylinder is then filled with fnlnrinating-powder, and the cylinder driveninto the cup, as heretdore.

The cup may have been charged with the saure fulnrinathrg-lmwder, or with a cheaper powder.

The two insulated wires are usually made into a cor-d,I by twisting them together. It is frequently nccessrry atterward to separate the wires for several yards, when many blasts are to be made at one time.

But when wires twistedinto a. cord are to be separated, it takes a. good deal of time to untwist them,

and the untwisting may disarrange the blasting-appa.-

A atns.

I have devised a method of uniting the wires which obviates these diilicultics.

The two wires having been laid together, as nearly parallel as possible, l wind -a weak cotton thread around thenr, in such a. manner, that at each turn the thread shall advance a. considerable distance on the wires, as seen in Figure 2, where al and e are the insulated wires, and o, the thread.

When it is necessary to separate the wires, it can be readily done, by simply pulling them apart, as the thread breaks easily, and allows the wires to separate without becoming entangled together or with the uniting-thread.

the separat-ion of the wires, as above described, will be of use for electrical purposes, when notconnected with a.. fuse.

The'wires thus united should be dipped into a s0- hrtion, which, upon drying, leaves it water-proof. I prefer for this purpose Chattertons compound.

After thc wires have been'securcd within the fuso,A

as previously directed, the wooden shell is dipped into paraliiue. This makes tho fuse water-proof.

To prevent the disk .7: from splitting when driven, two small nicks are made in its `periphery, for the recept-ion ofthe wires.

I claim- 1. Securing the ends of the insulated wires within the, shell of the fuse. by a disk, substantially as described. y

2. Uniting the two pruallel insulated wires by a nou-conducting thread; substantially 'as described, to allow the wires to be separated, as specified.v

The above specification of mysaid invention, signed and witnessed at Boston, this 21st day of J une, A. l).

H. J ULIUS SMITH. 'it-ncsscs:

W. W. SWAN, W. H. J AcKsoN. 

